Boiler Fittings (7)

Following previous articles on the boiler fittings, here's some photogenic progress:

RHS Gauge Glass Valves & Protector

In an attempt to check that the gauge glass valves and protector fitted correctly, I placed them on the right hand boiler location.

I'm glad to say that they fitted perfectly although the boiler studs will need shortening so the nuts don't foul the valve mechanism.

Sentinel 7109's gauge glass valves are different to ones that can be bought off the shelf today. As a result, off the shelf protectors wouldn't fit without being modified.

Whilst visiting family in Wakefield, I made a trip to Chanter Biomed Ltd in Bradford, Yorkshire, seemingly the only company to be still making these fittings in the UK.

On being able to handle the Sentinel valves, CB were able to turn out a special pair of made-to-measure protectors overnight. I was really pleased as this meant they were bought, made and collected within 24 hours. It's a pleasure to receive that kind of service so CB are definitely on my list of preferred suppliers for the future!

Domestic Help

After pressure washing the water tank walls to remove scale and rust debris, I managed to finally dry the inside of the tank by dangling a domestic vacuum cleaner in the tank so that it inhaled air from the tube outside and exhaled it down inside the tank. Sorry no photo but I confess I did feel just a little smug at thinking up that idea!

Some remaining debris could now be seen so I repeated the earlier vacuum cleaner treatment complete with long extension handle.

Domesticity reigns

Right down there; it's about eight feet to the bottom.

Long range sucker

Now the tank is ready for use.

Pipes Up

Following on from the last pipework article, here's a couple of photos to illustrate the somewhat awkward item of pipework which Mendip Steam Restorations are going to re-fabricate for Sentinel 7109.

Round the bend (1)

As well as needing to have the shape exactly right, the fittings at each end have to be correctly orientated. It won't be an easy task. It seems that Sentinel were very keen on rigid rather than flexible pipework; hence accuracy is required on both counts.

Round the bend (2)

I've also been adding to the exhaust pipework which now rises between the cab front and the boiler itself. This is the first time these pipes have been attached since 7109 arrived in December 2004.

Onwards & Upwards through a hole in the cab floor

Upwards to the boiler top between the cab front and boiler

The boiler top is starting to look populated!

At the boiler top

Now that components are being fitted that have never been attached to 7109 since its arrival at Midsomer Norton, it definitely feels like we're entering the home straight towards steaming.

Pipe Further Back

In the previous article about pipework, I left things in suspense regarding the steam pipe that has to circumnavigate the boiler. This is the one which needs to be replaced as it is badly pitted by corrosion. (More suspense later).

Before vandalising the old pipe, it seemed like a good de-risking exercise to temporarily try it in place as originally it arrived separated from the loco back in 2004.

Pipe curving down from the regulator

This photo is somewhat clearer than the only previous one I had.

The pipe passes to the right of the boiler and out through a gap left for it towards the front of the cab...

Out through there!

... and thence to the rest of the steam pipe below.

To here, between the lower boiler and cab front

These photos show the corrosion on the pipe's outer surface. Oddly, the corrosion looks as if it was due to water being retained in the external pipe insulation rather than from inside as might be expected.

Below the water tank

The 5th, 7th and 8th April also saw the front two sections of the exhaust pipes fitted.

A suspense picture!

Remember Remote Control 1927 Style?

Now the engine bay is looking more like spaghetti junction with the pipework back in place!

Not an easy workspace!

There's still a lot to do but it does seem like a lot of progress is being made at the moment (let's hope the rain keeps away!).

Many thanks to the kind gentleman who made a healthy donation to the restoration recently. Much appreciated.

Sentinel 7109's Mechanical Lubricator - A Second Mystery Solved

The first mystery was solved in my previous article on the subject. I'd been wondering why there should be a short pipe leading from one of the exhaust pipes to the base of the mechanical lubricator.

Pipe ends highlighted

I'd heard that the pipe was to help heat the lubricator using exhaust steam; however, I could not see how this worked as there did not seem to be anywhere for the steam to escape at the lubricator end.

I was told recently that there should be a hole for the steam to escape but wasn't told where it was likely to be located. On previous occasions, I'd not found anything resembling a hole anywhere. However, as I am currently in the process of refitting the exhaust pipe concerned, I decided that I would have to look a good deal harder.

I detached the pipe from the lubricator. Initially, I still couldn't find a hole but then I began to unscrew the lubricator fitting and spotted what looked like a centre punch indent. I scraped at it with a piece of wire and a hole appeared.

Lubricator pipe fitting

There it is!

Blowing in some air demonstrated that there really was a route for the steam from the pipe to the little orifice.

So a mystery solved and yet another of a Sentinel's peculiar steam outlets found.

Pipe Back

After the steam pipe down from the engines to the underneath comes the pipe beneath the water tank leading back towards the boiler.

Down to back pipe joint (sealed using a copper washer)
(Compare with this)

The pipe is supported by two orange 'U' brackets attached to the tank underside.

Brackets in orange

At the boiler end, the pipe curves upwards and towards the off-side to meet the next pipe section which circumnavigates the boiler.

Curving up and towards the boiler's off-side...

...like this!
(The engine-mounted BFP Water pipes to the boiler are on the right)

Then things get more difficult. The pipe that circumnavigates the boiler needs to be renewed as it was badly pitted with rust on arrival. Regrettable, I don't have a photo of it; however, the best I can do for now is a heavily processed and cropped old photo showing part of it.

Pipe curving down from the regulator assembly

This pipe is not simply curved in one plain but in two, i.e. it has to curve both down and round the boiler.

Mendip Steam Restorations have agreed to take on this job which will mean removing the old fittings for reuse and making the pipe in two sections. The sections will then be welded together in situ to be sure that they fit correctly. It would be difficult to do a drawing for this!

By making the two ends separately, the complexity of the curves can be reduced to a practical level.

In the meantime, I'll be fitting the exhaust pipes from the engines to the chimneys - which means the chimney repairs need doing urgently!